Caulking gun and cartridge therefor



May 6, 1958 w. A. SHERBONDY CAULKING GUN AND CARTRIDGE THEREFOR Filed Jan. 17, 1957 2,833,45l Patented May s, was

United States Patent Ollice 2,833,451 CAULKING GUN AND CARTRIDGE THEREFOR William A. Sherbondy, Cleveland,0hio Application January 17, 1957, Serial No. 634,691 2 Claims. (Cl. 222-327) The present invention relates generally as indicated to a caulking gun and cartridge therefor, and more particularly, to a caulking assembly that employs a disposable cartridge having a dispensing spout at one end and a piston at the other end.

Caulking guns that employ such disposable cartridges are of course, well-known in the art, and for the most part, they comprise a gun which supports the cartridge and which is provided with a lever-actuated plunger that is adapted to engage and to move the cartridge piston toward the spout. Thus, axial movement of said piston exerts pressure on the caulking material and displaces the same through the dispensing spout of the cartridge. An annoying problem encountered with this type of caulking assembly is that when the assembly is set aside after use, the caulking material remaining in the cartridge expands and thus oozes or drips from said spout, this evidently being due to the relatively high compressibility and relatively slow recovery of the caulking material, and, perhaps to some extent, especially'with a paper cartridge, to slight swelling of the cartridge body. The expression of the caulking material from the spout builds up pressure in the cartridge with resulting compression of the material which, unless permitted to expand within the cartridge, will subsequently expand through the spout. This oozing problem has been solved by me in a number of different ways, one of which is to use a composite cartridge piston comprising an outer ring that has a tight sliding fit in the cartridge body to prevent leakage, an inner ring telescoped within said outer ring, and a flexible diaphragm or membrane clamped between said rings to extend across the opening in said inner ring. I have also developed a two-piece cartridge piston in which the laterally flexible diaphragm or membrane, has its periphery wedged between a sup:

porting ring and the inner wall of the cartridge. The 4 cartridge pistons formed as above, have a flexible center portion that permits the caulking material to expand freely thereby bulging the diaphragm through the opening in the inner ring or in the supporting ring as the case may be, whereby expansion of the caulking material is accommodated by such laterally flexible diaphragm in preference to the material oozing out of the dispensing spout. The foregoing inventions are disclosed in my copending applications, Serial No. 532,087, filed Sep tember l, 1955, now Patent No. 2,778,541, dated Jannary 22, 1957, and Serial No. 614,960, filed October 9, 1956.

It is a principal object of this invention to provide a caulking assembly and cartridge that achieves the desired results in somewhat the same manner as disclosed in said copending applications, but which effects further simplification of the structure and substantial economies in the manufacture of the caulking assembly and cartridge.

Other objects and advantages of the present invention will become apparent as the following. description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

Fig. l is a side elevation view, partly in cross section, showing a preferred form of this invention; and,

Fig. 2 is a fragmentary cross section view on somewhat enlarged scale showing the laterally flexible closure wall of the cartridge as laterally flexed by the expansion of the caulking material when the axial force of the caulking gun is released.

Referring now in detail to the drawing, the caulking gun is generally designated by the reference numeral 1, and includes the usual form of handgrip 2, and a trigger or actuating lever 3, the latter being effective when pulled toward the handgrip 2' to actuate a ratchet mechanism cartridge 8, the dispensing spout 9 of which is inserted through the central opening of a plate 10 at the left end of said saddle 7. With the cartridge 8 positioned as shown in Fig. 1, the lever 3 may be actuated to cause the plunger 6 to enter the right-hand end of said cartridge.

The cartridge 8 itself, may comprise a thin sheet metal tube or a paper tube with metal reinforcing rings 11 and 12 at its ends, the reinforcing ring 12 at the left-hand end, serving to hold the dispensing spout 9 in place. Within the right-hand end of said cartridge 8 is a piston 14 which may be made of organic plastic material such as polyethylene, nylon, or like plastic, which is inert to the caulking material. Said piston 14 is integrally formed with a relatively rigid axially extending skirt which is snugly fitted in the cartridge 8 to prevent leakage of the caulking material, said piston 14 additionally being formed with a relatively thin and laterally flexible closure wall 16 extending across the opening in the skirt 15. The body 17 of cartridge 8, especially when made of paper, will generally be lined, as by spraying, with a suitable oil impervious material to prevent leakage or penetration of the oils of the caulking material through the wall of said cartridge body.

Initially, such closure wall 16 will be bulged convexly outwardly as best shown in Fig. 2. However, when the plunger 6 is moved toward the left the bulge of said wall 16 will be reversed as shown in Fig. 1 and as the movement of the plunger 6 is continued toward the left the peripherial flange of said plunger 6 will engage the inturned flange of the skirt 15, whereupon the piston 14 will be bodily moved toward the left to displace the caulking material under pressure through the dispensing spout 9.

Now, when the rod 5 is turned, as shown in Fig. 2, the expansion of the caulking material will cause said closure wall to bulge convexly outwardly and such lateral flexing of said closure wall occurs with such ease that the caulking material will not have an opportunity to ooze or drip from the end of the dispensing spout. Thus, when the present caulking assembly is set aside after use, there will of the plunger When the plunger 6 the diameter of the skirt 15 will be 1 inches for use with a paper cartridge body 17 having an inside diameter 7 of such wall and then to engage said piston near the periphery thereof whereby caulking material in said cartrid'ge is displaced under pressure through said spout rewhich renders said closure wall easily flexed from the Y position of Fig. 1 to that of Fig. 2 and vice-versa. In the specific example given, the amount of bulging at the center of the closure wall 16 may be from about inch to /2 inch. Such amount of bulge will easily accommodate the amount of expansion of the commonly used caulking materials.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims, or the equivalent of such, be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A caulking assembly comprising a cylindrical cartridge having, at its respective rear and front ends, a piston and a dispensing spout; said piston being integrally formed with an axially extending skirt that snugly fits within said cartridge so as to seal the cartridge and so as to, remain at progressively advanced positions toward said spout and with a thin laterally flexible closure wall that is initially bulged convexly rearwardly of said cartridge; a caulking gun for supporting said cartridge; said is shaped to initially laterally flex to rever e the bulge sponsive to axial movement of said piston toward said spout; said wall, upon release of axial force on said plunger, being flexed by the pressure of the caulking material with respect to said skirt so as to bulge convexly rearwardly, whereby, after use of said assembly, the expanding caulking material in said cartridge preferentially 10" flexes said wall instead of oozing from said spout.

2. A cartridge for caulking guns comprising a cylindrical body provided, at its respective front and rear ends, with a, dispensing spout and with an axially movable piston; said piston being integrally formed with an axially extending skirt that is a tight fit within said cartridge so as to seal said body and so as to remain at progressively advanced positions toward said spout and with a laterally flexible closure wall that is initially budged convexly rearwardly of said cartridge and that is adapted to be bulged concavely forwardly when said piston is axially moved toward said spout to displaced caulking material under pressure through said spout; said wall, upon release of axial force on said piston, being readily flexed with respect to said skirt to convex form to accommodate expansion of the caulking material and thereby preclude after-oozing of the caulking material from said spout when the cartridge is set aside after use.

References Cited in the file of this patent UNITED STATES PATENTS 2,098,524 Smith Nov. 9, 1937 2,111,582 CreWe Mar. 22, 1938 2,646,906 Jones et al. July 28, 1953 

